The study consists of measurement of antidepressant-induced excessive sweating and its treatment with an experimental medication, terazosin (approved for hypertension), that will be added to the antidepressant. This study is for people who take an antidepressant due to a depressive disorder. This is an open-label study (no placebo group) that will last 5 weeks, with one week of baseline measurement and four weeks of treatment with the study medication. The study is based on the hypothesis that terazosin will be effective in reducing the severity of excessive sweating caused by antidepressant treatment, and will have minimal side-effects.